package cn.ruituo.adv;

public class Stringstr4 {
    public static void main(String[] args) {
        StringBuilder sb=new StringBuilder();
        sb.append("nihao").append("java").append(Math.random()).append(2<1).append(32*23);
        System.out.println(sb);
        sb.delete(2,5);
        System.out.println(sb);
        sb.reverse();
        sb.insert(6,"大扎好");
        System.out.println(sb);

    }
}
